The manufacturers of engines and their associated machines are increasingly considering natural gas as a fueling option. One such strategy includes configuring a compression ignition engine to be supplied with both liquid diesel fuel and natural gas. In a typical scenario, a large charge of natural gas is ignited by first compression igniting a small diesel pilot injection quantity of fuel. U.S. Pat. No. 7,627,416, for example, teaches a method and apparatus for operating a dual fuel internal combustion engine when the primary fuel (e.g. natural gas) becomes unavailable, requiring operation of the engine with the secondary fuel (e.g. liquid diesel) alone. Thus, while the art recognizes a potential need to operate a dual fuel engine on some occasions using only liquid diesel fuel, designing and constructing a fuel system that is commercially viable has remained problematic. For instance, providing a fuel injector that can be appropriately controlled to not only inject tiny pilot quantities to compression ignite larger charges of gaseous fuel, while at the same time having the ability to inject relatively large quantities of liquid diesel fuel when the natural gas system is unavailable, provides two divergent constraints on the fuel system that are difficult to reconcile.
The present disclosure is directed toward one or more problems set forth above.